prefer the stack to the heap (+ don't refill the host list if already full)

[simgrid.git] / src / s4u / s4u_netzone.cpp

diff --git a/src/s4u/s4u_netzone.cpp b/src/s4u/s4u_netzone.cpp
index 5377233..0a343db 100644 (file)
--- a/src/s4u/s4u_netzone.cpp
+++ b/src/s4u/s4u_netzone.cpp
@@ -24,6 +24,7 @@ simgrid::xbt::signal<void(bool symmetrical, kernel::routing::NetPoint* src, kern
 NetZone::NetZone(NetZone* father, const char* name) : father_(father), name_(xbt_strdup(name))
 {
 }
+
 void NetZone::seal()
 {
   sealed_ = true;
@@ -72,16 +73,15 @@ NetZone* NetZone::father()
   return father_;
 }
 
-std::vector<s4u::Host*> NetZone::hosts()
+std::vector<s4u::Host*>* NetZone::hosts()
 {
-  std::vector<s4u::Host*> res;
-
-  for (auto card : vertices_) {
-    s4u::Host* host = simgrid::s4u::Host::by_name_or_null(card->name());
-    if (host != nullptr)
-      res.push_back(host);
-  }
-  return res;
+  if (hosts_.empty()) // Lazy initialization
+    for (auto card : vertices_) {
+      s4u::Host* host = simgrid::s4u::Host::by_name_or_null(card->name());
+      if (host != nullptr)
+        hosts_.push_back(host);
+    }
+  return &hosts_;
 }
 
 int NetZone::addComponent(kernel::routing::NetPoint* elm)